Anyone heard a video of what the car would sound like with just the cat delete downpipes installed and the rest of the exhaust OEM?

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I doubt you will find anything as I dont think anyone would do this.

The main reason to delete cats & add downpipes would be to increase flow and HP, but think the restrictive OEM exhaust & mufflers would defeat that purpose. If you’re going for more performance then curious why only do half the upgrade?

Anyone heard a video of what the car would sound like with just the cat delete downpipes installed and the rest of the exhaust OEM?

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Possibly going for a better sound but not to obnoxious is why keeping the OEM mufflers is a thought?
I have muffler delete plan on upgrading the exhaust more (not with bolt on exhausts) but in all due time since it sounds great with the muffler delete.
I have a video on my youtube channel.

The main reason to delete cats & add downpipes would be to increase flow and HP, but think the restrictive OEM exhaust & mufflers would defeat that purpose. If you’re going for more performance then curious why only do half the upgrade?

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I am looking at an eventual ECU tune on the car and have been told that the secondary cats are a point of restriction and a point of heat build up under the car. I was also looking at eventually doing the Kia bi-modal exhaust for a little more throaty sound outside the car, but minimal in-cabin increase in noise. My worry is: both done at the same time might result in too great an increase in the in-cabin noise, in which case you'll be reading my obituary when my wife gets done with me. So, if the downpipe and cat delete alone will increase exhaust noise on it's own, then I would stop there and leave the OEM mufflers in place. If no significant change in sound with the downpipes, then I can pursue the bi-modal exhaust when funds are available.

The ECU tune and cat delete will add more than enough oomph to the car. Changing rear mufflers would make an imperceptible difference in power at that point.

Are you asking about installing a new, catless downpipe or just deleting the cats on the OE downpipe?

Before buying a catback I did consider deleting the cats for a bit of extra sound and better flow. The factory downpipes aren't very restrictive once the cats are gone so I wouldn't bother swapping them out. The reason I didn't do it is because Tork MS said they had issues with the car throwing codes after removing the cats, even though the cats themselves have no O2 sensors. (look through their youtube videos for more information)

I think a better option for someone who doesn't want to spend a bunch of money, wants to increase the exhaust's flow, and wants more sound would be to swap out the stock resonators for aftermarket, high flow resonators.

Are you asking about installing a new, catless downpipe or just deleting the cats on the OE downpipe?

Before buying a catback I did consider deleting the cats for a bit of extra sound and better flow. The factory downpipes aren't very restrictive once the cats are gone so I wouldn't bother swapping them out. The reason I didn't do it is because Tork MS said they had issues with the car throwing codes after removing the cats, even though the cats themselves have no O2 sensors. (look through their youtube videos for more information)

I think a better option for someone who doesn't want to spend a bunch of money, wants to increase the exhaust's flow, and wants more sound would be to swap out the stock resonators for aftermarket, high flow resonators.

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OK, so now I'm confused!

I was under the impression that the Stinger had a 2 stage downpipe: short primary downpipe right after the turbos that have the primary cats with sensors that control emissions; and secondary longer downpipes that have the secondary cats with no sensors and no effect on emissions control (these are the ones that Jun BL sell without the cats). Tork MS suggested that I delete the secondary cats as they found a restriction and heat build-up related to the secondary cats. If I'm wrong, please feel free to correct me.

I was under the impression that the Stinger had a 2 stage downpipe: short primary downpipe right after the turbos that have the primary cats with sensors that control emissions; and secondary longer downpipes that have the secondary cats with no sensors and no effect on emissions control (these are the ones that Jun BL sell without the cats). Tork MS suggested that I delete the secondary cats as they found a restriction and heat build-up related to the secondary cats. If I'm wrong, please feel free to correct me.

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My understanding is that the cats cause the most restriction, but the OEM mufflers and exhaust are very restrictive too and will cause back pressure. We're just stating that unless you "unclog" the muffler restriction too you wont see the gains your hoping for when deleting the cats & adding a downpipe.

I'm unsure about the 2 stage downpipes so ill let someone else chime in on those questions.

Jesus man..drive that thing. I get mine tomorrow and should be past the 1000km by Sunday! No idea when I am gettign the downpipes or magnaflow yet, so when I get it'll stage in in that order.

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Ha!! Funny!! 4.1 km to work from home. Only so many times I can do the main street Brockville on the way home!! Also leaving for a 2 week vacation in Greece in three weeks, so the Stinger will be parked in the garage for 2 weeks.

My understanding is that the cats cause the most restriction, but the OEM mufflers and exhaust are very restrictive too and will cause back pressure. We're just stating that unless you "unclog" the muffler restriction too you wont see the gains your hoping for when deleting the cats & adding a downpipe.

I'm unsure about the 2 stage downpipes so ill let someone else chime in on those questions.

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I understand what you're saying and that's why I'm looking at the bi-modal exhaust, but death by slow torture ("You ruined the car!!") is much worse than a few lost horsepower!!

What's also interesting is there was a thread on the forum of someone's build. He had the Jun EVC exhaust, with a
JB4 piggyback tune, and he dyno'd the car at various stages. If memory serves me correctly, stock tuning---closed to open valves=+10 HP. Tuned--closed to open valves=same HP--no difference. OEM mufflers maybe less of an issue with the increased boost?

Well I know magnaflow and borla has cat back kits for around 1200 so I'm leaning towards borla but will see and as for
intake I'll probably do the k&n kit last as the cold air
intake does very little for performance but more so for sound.

There are primary cats and secondary cats, both are on different sections of pipes. The downpipes have the secondary cats, and there are no O2 sensors. You won’t have CEL issues by slapping some downpipes on.

Tork was was running primary and secondary cat deletes. They had overboost issues with both primary AND secondary cats deleted.

Cats (non hi-flo) on any car are very restrictive. The primary cats on the Stinger are by far more restrictive mainly because the exhaust coming immediately off the turbos are about an inch in diameter and not true 2 1/4”.

What @Bear said. Tork deleted both cats and had overboost issues. They are running a ported primary cat and their catless downpipes with no issues. They are also using an upgraded intercooler and piping which increased boost. It may be possible to go completely catless with stock intercooler and not overboost.

What @Bear said. Tork deleted both cats and had overboost issues. They are running a ported primary cat and their catless downpipes with no issues. They are also using an upgraded intercooler and piping which increased boost. It may be possible to go completely catless with stock intercooler and not overboost.

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I'm looking at the ported driver's side primary cat, deleted secondary cats, and bimodal axle back exhaust but likely stick with stock intercooler as I live in a cooler climate. Looking forward to seeing Tork's final results. Should be eye opening!